EDP - Experimental Digital Photography

Mostly our camera accessories work for us, but sometimes they get in the way. The Solution is a bit of do-it-yourself.

Over recent months I have been experimenting with long exposure photography. To do this in normal daytime lighting requires the use of a very heavy neutral density filter or something like an infrared filter. These filters cut out so much light, sometimes eight to nine stops worth, that your full sun exposure stretches into minutes.

One of the filter systems I have been using is that by the French company Cokin. This system uses square resin filters and a filter holder that you fit to your lens. This is a great system and works extremely well in normal situations with normal filters. However, what I found in actual use with these very dark (effectively opaque to the eye) is that the filter holder allowed light to leak in behind the filter and fog the exposure. With such extreme filters there was nothing that you could do to cut it completely. I tried draping a cloth over the filter holder but this only helped a little. This is not an issue with the screw in filters because they have a tight fit to the lens.

The solution was a bit of do-it-yourself. The standard Cokin filter holder has three slots to take multiple filters. But even with a filter in the slot closest to the lens there is still a gap that lens can leak through. So what I decided to do is to glue some black leather scraps that I had lying around the filter holder so that with a filter inserted the leather sits up against the filter but still allows the filter to be slid in or out without scratching.



With these modifications in place most of the flare was gone. One more thing had to be done. I needed to use the eyepiece cover incorporated into the camera strap of my Canon 400D. Without it in place it was clear that some light was leaking around the mirror when it was up. With the cover in place (oh how I dream for a camera with a built-in blind) there was no more leakage and the images were clear and sharp.

Don’t be scared to modify your gear if you need to. The results can be great.

Coming out of a discussion on the dfa Yahoo list I put out a very rough list of features for what I saw as the ideal inkjet printer for digital artists. So I have decided to flesh that rough idea out here.
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